Dermal Fillers Is the treatment painful? The treatments are carried out using local anaesthetic. This may be a topical cream or a dental local anaesthetic. If lips are treated a dental local anaesthetic block is given. This will ensure minimal discomfort. How long does the effect of treatment last.? This depends on the patient and the site being treated and can vary. Generally speaking lip treatments last around six months and treatment for lines and wrinkles between six months to a year. A further treatment can be performed at any time ( you do not have to wait for six months). There is some evidence that the effects last longer after several treatments. Is this a new treatment? Restylane was introduced over ten years ago and worldwide more than one million treatments have been carried out. There are very few reported incidences of adverse reactions to Restylane. Hyaluronic acid products are used safely in other areas of medicine with great success eg urology.